Ball grid array (BGA) is fast becoming the package of choice in the surface mount technology arena. BGAs offer many advantages over standard fine-pitch surface mount and pin grid array technologies. These advantages include reduced placement problems since BGAs are self-centering, reduced handling issues because there are no leads to damage, lower profile and higher interconnect density. There is, however, a significant drawback with BGA technology: the lack of established BGA test accessories and procedures.
Electronic test instruments (e.g., oscilloscope, logic analyzer, emulator) are used to analyze various electrical aspects of the IC including voltage and current waveforms. Typically, a loaded printed circuit board is crowded with various electrical components, including multiple IC packages. Due to the close spacing of components on the board (i.e., high "board density") it is often difficult to electrically connect the ICs to the test instrument. BGAs only exacerbate this problem since there are no "leads" to access for testing purposes.